Deck 10: Muscle Tissue

Question 1

Invaginations of the muscle cell membrane that extend deep into the cell are known as the

A) T-tubules.
B) terminal cisternae.
C) titin complexes.
D) Z-discs.
E) end plates.

Answer 1

A

Question 2

Which are possible functions of skeletal muscles?
A: Maintenance of posture
B: Both highly coordinated and localized simple movements
C: Temperature regulation
D: Support of certain body organs
E: Regulation of the movement of material through certain body tracts

A) a, b, e
B) a, b, c
C) a, b, c, e
D) a, b, c, d
E) a, b, c, d, e

Answer 2

E

Question 3

Because skeletal muscle cells are so close together, muscle contains very few blood vessels.

Answer 3

False

Question 4

The structure responsible for attaching muscle to bone is a

A) sphincter.
B) ligament.
C) fascia.
D) tendon.
E) myofibril.

Question 5

In general, a skeletal muscle is composed of
A: connective tissue sheaths
B: nerves
C: arteries
D: veins
E: muscle fibers

A) a, b, c, e
B) a, b, d, e
C) b, c, d, e
D) a, b, c, d
E) a, b, c, d, e

Question 6

The property of muscle tissue that allows an impulse to travel down the entire length of the cell membrane is

A) elasticity.
B) conductivity.
C) extensibility.
D) contractility.
E) responsibility.

Question 7

The floor of the pelvic cavity includes skeletal muscles that function to support organs in that cavity.

Question 8

Which are the reservoirs that store the calcium required for muscle contraction?

A) Synaptic vesicles
B) Synaptic clefts
C) Terminal cisternae
D) Peroxisomes
E) Mitochondria

Question 9

The characteristic of muscle that allows it to be passively stretched is

A) conductivity.
B) elasticity.
C) excitability.
D) extensibility.
E) contractility.

Question 10

Deep fascia is also known as muscular fascia; it is composed of dense irregular connective tissue.

Question 11

The neurons that stimulate muscle contraction are called ________ neurons.

A) sensory
B) contractile
C) inhibitory
D) motor
E) association

Question 12

Which is a correct listing of the hierarchy of a skeletal muscle's components, beginning with the smallest?
A: Myofibrils
B: Muscle fiber
C: Fascicle
D: Skeletal muscle

A) a, b, c, d
B) a, c, b, d
C) d, c, b, a
D) c, b, a, d
E) b, c, a, d

Question 13

A circular muscle band that contracts at an orifice is also known as a ________.

Question 14

A flat, thin structure made of dense connective tissue that serves to attach a muscle to a bone (or to another muscle) is a(n)

A) aponeurosis.
B) tendon.
C) perimysium.
D) myolemma.
E) superficial fascia.

Question 15

The spring-like property that returns muscle to its original length after a contraction ends is

A) extensibility.
B) elasticity.
C) contractility.
D) treppe effect.
E) conductivity.

Question 16

The membranous network that wraps around myofibrils and holds relatively high concentrations of calcium is known as the

A) sarcolemma.
B) T-tubule.
C) sarcoplasmic reticulum.
D) sarcomere.
E) Golgi body.

Question 17

Satellite cells are multinucleate.

Question 18

Which is the correct order of the connective tissue layers of a skeletal muscle, beginning with the most superficial?
A: Endomysium
B: Epimysium
C: Perimysium

A) a, b, c
B) b, a, c
C) c, a, b
D) b, c, a
E) c, b, a

Question 19

The multiple nuclei in skeletal muscle cells are the result of the

A) fusion of myoblasts.
B) cytokinesis of embryonic satellite cells.
C) spontaneous development of nuclei in embryonic cells.
D) stimulation of fibroblasts by hormones.
E) action of testosterone on mesenchyme cell.

Question 20

The connections between the nervous system and skeletal muscle allow for voluntary control of movement.

Question 21

Which letter is associated with a zone (in a relaxed muscle) that is a little more lightly shaded because only thick filaments are present?

A) I
B) A
C) M
D) Z
E) H

Question 22

A typical skeletal muscle cell contains approximately ________ mitochondria.

A) 3
B) 30
C) 300
D) 3000

Question 23

Which protein makes up the thick filaments?

A) Myosin
B) Actin
C) Tropomyosin
D) Troponin
E) Myopathy

Question 24

Fibers from one motor unit

A) are clustered together within one fascicle of the muscle.
B) are dispersed throughout most of the muscle.

Question 25

Which is not a protein found in thin filaments?

A) Actin
B) Troponin
C) Tropomyosin
D) Myosin
E) No exceptions; all are found in thin filaments

Question 26

Which of the following structures has the active sites to which the heads of the thick filaments will bind?

A) Actin
B) Troponin
C) Tropomyosin
D) Myosin
E) Sarcoplasm

Question 27

A motor unit within the powerful quadriceps muscle would

A) contain several motor neurons.
B) be much like those in the eye muscles.
C) generally contain less than ten fibers.
D) generally contain several hundred fibers.

Question 28

________ is a protein that anchors myofibrils that are adjacent to the sarcolemma to proteins in the sarcolemma.

Question 29

Each thick filament contains about ________ protein molecules (each molecule has two heads and two braided tails).

A) 2
B) 20
C) 200
D) 2000

Question 30

Which letter is associated with the line that is a thin protein structure that serves as an attachment site for thin filament ends?

A) I
B) A
C) Z
D) M
E) H

Question 31

Muscles that are used for precisely controlled movements generally contain large motor units.

Question 32

One feature that helps provide fast energy to a muscle cell is the presence of granules containing the complex carbohydrate

A) creatine phosphate.
B) myoglobin.
C) glycogen.
D) nebulin.
E) hemoglobin.

Question 33

The presence of mitochondria and myoglobin facilitate ________ respiration in muscle cells.

A) aerobic
B) anaerobic

Question 34

A motor unit consists of

A) multiple motor neurons and multiple muscle fibers.
B) a single motor neuron and the multiple muscle fibers it controls.
C) multiple motor neurons and the one muscle fiber they control.
D) one synaptic terminal button, a cleft, and an acetylcholine receptor.
E) an end plate, a T-tubule, and sarcoplasmic reticulum.

Question 35

The narrow space that separates the motor neuron and the skeletal muscle fiber in a neuromuscular junction is called the

A) motor end plate.
B) synaptic vesicle.
C) synaptic cleft.
D) synaptic knob.

Question 36

Which letter is associated with the light band and contains thin filaments only?

A) I
B) A
C) M
D) Z
E) H

Question 37

A sarcomere is defined as the distance from one ________ to the next adjacent ________. (The same answer fills in both spaces.)

A) Z disc
B) I band
C) H zone
D) A band
E) M line

Question 38

Myoglobin is a molecule within muscle cells that can bind

A) creatine phosphate.
B) oxygen.
C) hemoglobin.
D) acetylcholine.
E) ATP.

Question 39

A skeletal muscle cell contains hundreds to thousands of ________, which are complex organelles; they are cylindrical in shape-about 2 micrometers in diameter and as long as the cell.

A) myofibrils
B) microfilaments
C) sarcomeres
D) T-tubules
E) sarcolemma

Question 40

What is the letter associated with the dark bands in a sarcomere?

A) I
B) A
C) Z
D) M
E) H

Question 41

During which phase of the crossbridge cycle is ATP split into ADP and P_i?

A) Immediately preceding the detachment of the myosin head
B) Immediately preceding the resetting of the myosin head
C) Immediately preceding the power stroke

Question 42

An end plate potential is an event that involves a gain of

A) positive charge along the inside of the cell membrane, as potassium rapidly enters.
B) positive charge along the inside of the cell membrane, as sodium rapidly enters.
C) negative charge along the inside of the cell membrane, as potassium rapidly enters.
D) negative charge along the inside of the cell membrane, as sodium rapidly enters.

Question 43

A drug that inhibited acetylcholinesterase would result in

A) a failure to stimulate the muscle due to decreased ACh release.
B) enhanced stimulation of the muscle due to decreased ACh breakdown.
C) enhanced stimulation of the muscle due to enhanced ACh release.
D) poor muscle stimulation due to enhanced ACh breakdown.

Question 44

The calcium ions involved in skeletal muscle contraction bind to a(n) ________ subunit.

A) myosin
B) actin
C) elastin
D) tropomyosin
E) troponin

Question 45

Which structures are reservoirs that store acetylcholine?

A) Synaptic vesicles
B) Synaptic clefts
C) Terminal cisternae
D) Lysosomes
E) Sarcomeres

Question 46

Phosphate transfer is used for

A) immediate ATP needs and is dependent on oxygen.
B) immediate ATP needs and is not dependent on oxygen.
C) long-term ATP needs and is dependent on oxygen.
D) long-term ATP needs and is not dependent on the presence of oxygen.

Question 47

Relaxation is facilitated by the release of passive tension that developed in cablelike ________ proteins that were compressed during contraction.

Question 48

Acetylcholine is released from a neuron

A) by a primary active transport pump.
B) by rapid diffusion when a voltage-gated ion channel opens for it.
C) through exocytosis when a vesicle fuses with the membrane.
D) by conduction through a gap junction from nerve to muscle.

Question 49

The repolarization of the action potential involves the opening of

A) chemically gated Na⁺ channels.
B) voltage-gated Na⁺ channels.
C) chemically gated K⁺ channels.
D) voltage-gated K⁺ channels.

Question 50

Acetylcholine exerts its effect by

A) stimulating the motor neuron's synaptic knob.
B) binding to receptors at the motor end plate.
C) activating acetylcholinesterase.
D) allowing calcium to enter the cell.

Question 51

For relaxation to occur,

A) calcium leaves the sarcoplasmic reticulum, and troponin binds calcium and blocks the binding sites on actin.
B) calcium enters the myofibril, it detaches from myosin, and the binding sites on myosin become inactive.
C) sarcoplasm calcium levels fall, calcium is removed from troponin, and tropomyosin blocks binding sites on actin.
D) extracellular calcium levels fall, calcium is pumped into the myofibril, and tropomyosin slides away from actin.

Question 52

When an impulse arrives at the knob of the motor neuron, calcium

A) enters through active transport pumps and triggers the release of transmitter.
B) enters through voltage-gated channels and triggers the release of transmitter.
C) exits through active transport pumps and brings transmitter with it.
D) exits through voltage-gated channels and triggers transmitter release.
E) is released from synaptic vesicles.

Question 53

Which is the neurotransmitter that causes the release of calcium ions from reservoirs within the muscle cell and thereby initiates the steps of contraction?

A) Acetylcholinesterase
B) Acetylcholine
C) Serotonin
D) Norepinephrine

Question 54

Myosin kinase catalyzes the transfer of P_i from creatine phosphate to ADP.

Question 55

The action potential of a muscle fiber occurs

A) at the end plate.
B) along the sarcolemma and down the T-tubules.
C) within the sarcoplasmic reticulum.
D) in the mitochondria.

Question 56

When a muscle relaxes,

A) crossbridges form and muscle extensibility returns the muscle to rest length.
B) crossbridges form and muscle elasticity returns the muscle to rest length.
C) crossbridges stop forming and muscle elasticity returns the muscle to rest length.
D) crossbridges stop forming and muscle extensibility returns the muscle to rest length.

Question 57

The neuromuscular junction is usually located at one of the two ends of the muscle fiber.

Question 58

Which sequence correctly lists the changes that allow the thick and thin filaments to slide past one another in skeletal muscle contraction?

A) Attach - pivot - detach - return
B) Pivot - attach - return - detach
C) Attach - detach - pivot - return
D) Return - pivot - attach - detach
E) Pivot - attach - detach - return

Question 59

For relaxation to occur,

A) ACh receptors close and Ca⁺⁺ channels on the sarcoplasmic reticulum close.
B) ACh receptors close and Ca⁺⁺ channels on the sarcoplasmic reticulum open.
C) ACh receptors open and Ca⁺⁺ channels on the sarcoplasmic reticulum close.
D) ACh receptors open and Ca⁺⁺ channels on the sarcoplasmic reticulum open.

Question 60

A power stroke involves

A) an actin molecule pulling a myosin molecule toward the M-line.
B) a thin filament shortening in length and thereby shortening the sarcomere.
C) a myosin head pulling a thin filament toward the center of the sarcomere.
D) a thick filament pushing an actin filament towards the nearest Z-line.

Question 61

The electron transport system refers to oxidative phosphorylation using the coenzymes FADH₂ and ________.

Question 62

In general, fast-twitch fibers generate less power than slow-twitch fibers.

Question 63

The contraction phase of a muscle twitch has a shorter duration than the relaxation phase.

Question 64

Events of excitation contraction coupling, such as the release of calcium from intracellular stores, occur during the ________ period of a muscle twitch.

A) relaxation
B) contraction
C) latent

Question 65

Compared to slow-twitch fibers, fast-twitch fibers respond to a stimulus with less delay and with a shorter contraction duration.

Question 66

The vascular supply to slow-twitch muscle fibers is ________ the network of capillaries around fast-twitch muscle fibers.

A) more extensive than
B) less extensive than
C) the same as that of

Question 67

Glycolysis is an

A) aerobic process that occurs in the cytosol.
B) aerobic process that occurs in the mitochondria.
C) anaerobic process that occurs in the cytosol.
D) anaerobic process that occurs in the mitochondria.

Question 68

The type of fibers specialized to continue contracting for extended periods of time, as would be required in running a marathon, for example, are ________ fibers.

A) fast-twitch
B) slow-twitch
C) intermediate

Question 69

Muscles of the eye and hand have a high percentage of ________ fibers.

A) fast-twitch
B) slow-twitch

Question 70

Oxidative fibers are

A) red and fatigue-resistant.
B) red and fatigable.
C) white and fatigue-resistant.
D) white and fatigable.

Question 71

Heavy breathing to compensate for an oxygen debt helps the body convert lactate to glucose.

Question 72

"Intermediate fiber" is another name for

A) a fast-twitch, glycolytic fiber.
B) a fast-twitch, oxidative fiber.
C) a slow-twitch, glycolytic fiber.
D) a slow-twitch, oxidative fiber.

Question 73

One's genes have a greater impact than exercise habits in determining the proportion of fast-twitch and slow-twitch fibers throughout the body.

Question 74

Which fibers dominate many of the back and calf muscles that contract almost continually to maintain posture?

A) Slow-twitch
B) Fast-twitch
C) Intermediate

Question 75

For a sprint lasting 60 seconds, ATP is supplied primarily by

A) aerobic respiration only.
B) phosphate transfer and glycolysis.
C) conversion of lactate to pyruvate.
D) phosphate transfer only.

Question 76

The net energy yield from one glucose molecule through the process of glycolysis is

A) 2 ATP.
B) 6 ATP.
C) 30 ATP.
D) 36 ATP.

Question 77

Aerobic respiration involves the oxidation of pyruvate.

Question 78

Glycolytic muscle fibers tend to be very rich in myoglobin and mitochondria.

Question 79

When someone engages in exercise that requires more oxygen than is available, they develop a(n) ________ (2 words), which results in heavy breathing for several minutes after the exercise is complete.

Question 80

If someone is engaged in six minutes of vigorous exercise, nearly all of the ATP used is generated by phosphate transfer.